Machining conditions are controlled by three geometric-rate quantities:

• cutting speed $V$: relative speed of the cutting edge through the workpiece surface;
• feed: advance of the tool per revolution, tooth or unit time;
• depth of cut: thickness of material removed normal to the generated surface.

For turning a cylindrical workpiece of diameter $D$ rotating at $N$ revolutions per minute,

$$V=\pi D N,$$

provided units are chosen consistently.

If feed per revolution is $f$ and radial depth of cut is $d$, an approximate material removal rate is

$$\mathrm{MRR}=Vfd.$$

For example, with $V=120\ \mathrm{m/min}$, $f=0.20\ \mathrm{mm/rev}$ and $d=2.0\ \mathrm{mm}$,

$$\mathrm{MRR}=120000\times0.20\times2.0 =48000\ \mathrm{mm^3/min}.$$

Increasing these parameters can increase productivity, but they do not have identical consequences. Higher speed often raises tool temperature and wear strongly. Larger feed typically increases chip load and surface roughness. Greater depth of cut increases engagement and force.

A productive machining condition therefore balances removal rate against machine power, tool life, stability, dimensional accuracy and surface requirements rather than maximizing any one parameter.